This tutorial explains how to replace the air cabin filter - dust pollen filter on our favourite car the BMW 3 Series E46.
This video is valid for all kind of engines: diesel and gasoline.
This operation must be done each 15.000 Km or at least yearly. The filter is cheap, it cost no more than 15 € and could be buyed in nearly every auto parts shop. It's a very important car maintenance operation in order to maintain the air inside the car on a good condition.
I hope you will find this video tutorial useful!